Influence of fiber prestressing on strength of polymer composite material

The present study is a theoretical and experimental research of polymer composite strength with fibers subjected to pre-tension during manufacturing, similar to prestressed reinforced concrete. After matrix hardens and tensile load is removed off fibers, tensile stress remains in the fibers, creating compressive stress in the matrix. To a greater extent prestress increases the crack resistance limit of the matrix, as well as the elastic limit, strength and elastic modulus of the composites. Theoretical analysis proved a significant increase in strength in the pre-tension direction. The experiment showed that an increase in the strength properties of fibers, especially elastic modulus and tensile strength, increases mechanical properties of resulting composite. The results obtained allow us to recommend the introduction of fiber prestressing technology into industry. The subject of further research is to determine the degree of prestress, optimize the parameters of the composite, its mechanical and physical properties, and improve the technology of prestress.